Shell-like fruit, not soft (3)
I believe the answer is:
ear
'shell-like' is the definition.
(I've seen this before)
'fruit not soft' is the wordplay.
'fruit' becomes 'pear' (pear is a kind of fruit).
'not' is a deletion indicator.
'soft' becomes 'p' (musical abbreviation for piano, 'soft').
'pear' with 'p' taken away is 'EAR'.
(Other definitions for ear that I've seen before include "Organ of hearing" , "Attention; an organ" , "Shell-like (slang)" , "Discernment musicians need" , "Hammer in this" .)